z axis inverted in NC file

I had a fairly simple .nc file that I ran successfully a couple weeks ago. Today, when i load it, the Z axis is inverted. What could I possibly have done to cause this?  Running LinuxCNC 2.9.2.  I haven't changed any of my .ini or config files. could I have received some update automatically that flipped my Z axis?

Hard to know with such limited info, so:
-does jogging the axis work properly or is it inverted also?
-does the nc file contain negative values for Z axis?
-does the machine have homing switch on Z axis?

jogging the axis works fine. The machine has a homing switch on the Z axis at the top of its motion range. the .nc file is attached for reference.
 

No file.
And the ini is not set properly for a mill, the Z=0 must be the top point on the machine and everything below must be negative value, or in your case it should be Z min -5.
Despite that, it can work as is if you use the touch off.
And the above "must" is what is normally used, not written in stone.

Here is the .nc file I am trying to execute.